Associated PressBoston Red Sox outfielder Jacoby Ellsbury has hairline fractures of four ribs, but a return from the disabled list Tuesday has not been ruled out.

BOSTON - Boston Red Sox outfielder Jacoby Ellsbury has hairline fractures in four ribs, and while a return from the 15-disabled list Tuesday is still possible, it is by no means assured.

"Nothing is displaced. That's good news,'' Red Sox manager Terry Francona said Thursday, after Ellsbury had undergone a CT scan.

The Red Sox underestimated the extent of Ellsbury's injury, and so did the player. Playing left field, he collided with third baseman Adrian Beltre in Kansas City on April 11.

Ellsbury was convinced he would miss only a couple of days. The Red Sox thought so, too, and a CT scan was not taken until Thursday, 11 days after the injury.

"(Soon after the injury), we told him when the DL return date would be, and he said, no way (was that necessary),'' Francona said.

Instead, Ellsbury missed seven games over an eight-day period. Because he was still active, the Red Sox played with a short-handed roster, a situation exacerbated when centerfielder Mike Cameron missed two days with a kidney stone and then had an abdominal problem.

On Tuesday, both outfielders went on the disabled list. In Ellsbury's case, the move was retroactive active to April 12.

That means he is eligible to come off the DL Tuesday.

"This may not affect the timetable of his return, but maybe it will,'' Francona said.

The Red Sox had to decide by Wednesday whether to put Ellsbury on the DL in a retroactive manner. A 10-day window exists to make that decision.

They put him through a final workout Tuesday to see if that could be avoided. When the results were unsatisfactory, he went ont he disabled list.

Ellsbury told MLB.com he asked for Thursday's CT scan and MRI.

"For me, it just wasn't getting better," Ellsbury said. "I kind of asked for it, the MRI and the CT, and I'm glad I went about and did it, just to get some kind of closure of what was going on."

The 11-day gap between the injury and the CT scan is bound to raise questions of why the Red Sox waited so long.

"The medical people assured us that this is the protocol," Francona said.

"This is how you do it. You treat the symptoms. But once he wasn't able to play, then we need to go back and do the CT scan. Nothing is displaced.

"We had four people read the X-rays, and they said when the X-ray comes back negative, then you treat the symptoms.

Red Sox medical director Thomas Gill also said Thursday that the sequence of the procedure used in Ellsbury's case was standard.

General manager Theo Epstein said Tuesday that in hindsight, putting Ellsbury on the disabled list after the injury probably would have been the better move.

But Epstein did not second-guess the decision, saying the Red Sox made their decisions for sound reasons, based on the information available at the time.

Gill said it was impossible to pinpoint a return date.

"Sometimes, it can be a week. Sometimes it can be a couple of weeks,'' Gill said.

"As soon as he can swing, hit, run and catch, he'll be cleared to play.''

Ellsbury will wait at least a couple of more days before swinging a bat.

Cameron remains on the disabled list with an abdominal strain as well. He said Thursday he is feeling better, but Cameron will still be out a few weeks at least.